For SF_USER_NAME, enter the the username of your Salesforce integration user

For SF_PASSWORD, enter the the username of your Salesforce integration user

Step 4: Create a Facebook App

Follow these instructions to create a Facebook app. You'll have to create a Facebook page, a Facebook application, and configure Messenger for your application.

When asked for a Callback URL, enter the URL of the Heroku app you just deployed followed by /webhook. For example:

https://myapp.herokuapp.com/webhook

When the Page Access Token is generated, login to the Heroku Dashboard, and set the Heroku FB_PAGE_TOKEN config variable to the value of that token (Setting>Reveal Config Vars)

When asked for the Verify Token, enter the value you entered for the FB_VERIFY_TOKEN config variable when you deployed the Heroku app.

Make sure you select a page in the Select a page to subscribe your webhook... dropdown

Visit the Facebook page you created in the previous step, and click the Message button. Type help in the chat bot. You can continue the conversation with the bot in the Messenger app on your phone or in the browser (http://messenger.com).